NATURAL HISTORY STUDIES 



picture of the forever unseen a strange, dark, cold, 

 calm, silent, monotonous world ! 



No depth too deep for Life. It was proved by the 

 Challenger expedition that there is practically no 

 depth-limit to the distribution of animal life. 

 Wherever the long arm of the dredge has been able 

 to reach, there are organisms and plenty of them. 

 It is astonishing to read of Sir John Murray and 

 Dr. Hjort using an otter trawl, with fifty feet of 

 spread, at a depth of 2,820 fathoms (over three 

 miles), and using it very successfully. It should be 

 noticed that there are some thinly peopled areas 

 sea -floor deserts, so to speak ; that there is a richer 

 population at the more moderate depths ; that 

 there are more animals on the calcareous ooze than 

 elsewhere ; and that there are probably thinly- 

 peopled zones between the bottom and the light - 

 limit. But the big fact is that there is no " deep " 

 too deep for life. 



Plantkss. Another big fact is that, beyond the 

 sunk resting stages of some simple Algae, there are 

 no plants in the Deep Sea. This follows from the 

 absence of light, and it involves as a consequence 

 that all the Deep-Sea animals must be either carni- 

 vorous or devourers of debris. There are the usual 

 " nutritive chains " Deep-Sea fish eating Deep-Sea 

 crustacean, and that eating worm, and that eating 

 still smaller fry ; but since they cannot all be eating 

 one another there must be some extraneous food- 

 supply. That is found in the gentle and ceaseless 

 rain of small creatures, killed by changes in the 

 open-sea meadows overhead, and sinking through 



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